The problem I see with recruiting any of the ants to the crew is that their skill sets are arguably centuries out of date when it comes to working a modern starship in a high skill job.
I mean, being a marine is a pretty easily transferable skill set (and we know at least the red myr have an actual navy/marine corps; probably the golds as well). Myr of both colors are used to fighting in close quarters (ie tunnels) so they'd adapt pretty well to cqc in a ship's corridors.
Also, as the airborne beard pointed out: having a fuckable hole is a pretty solid crew qualification 'round these parts.